Ship&#39;s davit.



T. H. MARTEN.

SHIPS DAVIT.

APPLlCATION FILED JAN.2. 1911.

1,245,752. Patented Nov. 6, 1917.

2 SHEETSSHEET I- k I6 I 15 n I 1 Inventorn WMMWILQL Patented Nov. 1917.

2 SHEETS SHEET 2.'

T. H. MABTEN.

SHIP'S DAVIL ION FILED JAN.

' To all whom it may concern:

s'rATEs PATENT TEOKAS H. mums, OF IVE T N. Y.. ASSIGNOB TO MABTEN FREEMAN COMPANY LIMITED, F TORONTO, ONTABIO GANADA, A. CORPORATION.

SHIPS DAVIT.

Be it known that I, THOMAS HENRY MARTEN, a subject of the King of Great Britain, and resident of the city and State of New York, one of the nited States of America, haveinvented certainnew and useful Improvements in Ships Davits, as described in the following specification and illustrated in the accompanying drawings, that form part of the same.

This invention relates to improvements in ships. davits and particularly to that form of davit in which the boom swings in a vertical plane and is pivotally connected intermediate of its length to a movable member by means of which the swinging movement is controlled.

One or" the main objects of the invention is to minimize the longitudinal stress upon the means for swinging the boom, thereby reducing the labor of operating the boom.

A further object is to overcome'the difiiculties met with in taking up the slack and stretch in the falls and in clearing the boat from the chochs and in moving the boat outboard and inboard to clear the side of the ships deck. 7

Still further objects are to simplify the construction and to obtain the maximum rigidity and stability oi the davit.

1n the accompanying drawings, Figure 1 is a side elevational view of my improved davit showing the location of the parts in the extreme inboer and outboard positions.

Figs. 2 and 3 are small diagrammatic views illustratin the di'i 'erence' in the path of movement of boom head between machine having a horizontal path of movement for the int-erme "iate pivot of the boom and one having an inclined path of movement.

Fig. 4 is an enlarged longitudinal vertical sectional view through the bearing end of the boom operating spindle and through'the means for swinging the davit.

Fig. 5 is a vertical transverse section through the boom on the center line of its pivotal connection, the section being broken and showing the connection of the lower end of the boom.

Like numerals of reference indicate corresponding parts in each figure.

Specification of Letters Patent.

' beyond Patented Nov. 6, 1917.

Application filed .Tanuary 2, 1917. Serial No. 140,244.

connection with the boom operating means coincident with the outward movementthereof to counteract the downward tendency of movement of the boom head due to its mcreasing an iarity fromthe vertical.

In the application of the invention herein shown the frame 1 is preferably formed of cast-metal and isjsubstantially a' unitary structure of T shape section to give rigidity and strength. The end brackets 2 and 3 may or may not be formed integral with the frame and these are joined across the top by the top bar 4: which is also of a T-shaped section.

The upper side 5 of the main portion of the frame is of substantially T shape in cross section and the top surface thereof is arranged with an outward and upward incline and forms a trackway upon which a suitable carriage is adapted to travel.

The carriage 6 hereshown is formed with a pair of side flanges 7 adapted to overhang and engage the side edges 8 of the rail top 5 and is supported upon rollers 9 which travel upon said rail top, being journaled upon pins 10 extending between said side r I n nanges. The carriage is operated to move longitudinally upon the trackway 5 bymeans of a screw spindle. 11 which is journaled at the outer end in a bracket 3'and at the inner end in a be 12 i the bracket 2.

Edie ea 2 's here shown formed 01" 1 a balcon -.'l thrust type though any desire-ole bearing be adopted.

" perates .9 one. lugs is of the car- 1 pin secured in the carriage 6 midway set .v i the rollers 9 and extend the sides oi said cairiage.

16 is the boom which is here shown of the bifurcated type, though a solid type may be used if desired. The boom is pivotally connected intermediate of its length to the pivot,

pin 15, the lower end being here shown as being held by the pivotal link 17 but may be otherwise suitably connected or supported so as to insure its proper function in supporting the load in the outward travel of the boom head. A

The boom is shown in Fig. 1 of the drawings in its position of rest, sloping inboard from the vertical and it will be readily seen that upon the rotation of the screw spindle the carriage moves upwardly as well as outwardly upon the inclined track 5, in addi tion to the rise of the head due to the pivotal movement of the boom to the vertical position, consequently carrying the boom headfarther in an upward direction and thereby insuring the taking up of the slack and stretch in the falls and lifting the boat clear of the chocks.

As the outward movement of the boom is continued it swings upon its intermediate pivot and through the swinging movement the tendency of the boom head is to operate in an outward downward curve. This tendency is counteracted by the upward travel of the pivot with the result that the boom head and consequently the load operates in a path nearer to the horizontal and therefore less power is required to control the load than would be the case if the boom head moves in a more downwardly inclined path. This also insures the load being carried out-board to clear the siderail of the deck of the ship, thus obviating the dangers of fouling in the launching operation.

The ultimate result of this arrangement is that there is less drop and raise to the load as the boom is swung outboardaand inboard, thus minimizing the strain on the pivotal moving meansand therefore reducing the necessary power for swinging the davit.

The simple construction herein set forth obviates the necessity of complicated gearing in the davit and also simplifies the arrangement of the falls and insures a safe and easily operated device.

My inventionis herein shown as appiied to a davit in which the boom is connected at its lower end to a swinging link but it must be understood that the invention may be applied to other forms of davits if desired.

What. I claim as my invention is 1. In a ships davit, a frame, a boomsupported from said frame and adapted to swing in a vertical plane, means pivotally connected to said boom intermediateof its length for controlling the swinging movement thereof, and means for effecting a continuous upward movement of the point of connection between the boom and the boom controlling means coincident with the outward movement thereof to counteract the downward tendency of the movement of the boom head due to its increasing angularity. from the vertical.

2. Ina ships davit, a frame, a boom supported from said frame and adapted to swing in a vertical plane, means pivotally connected to said boom intermediate of its length for controlling the swinging movement thereof, and means for guiding the point of pivotal connection of the boom and boom controlling means upwardly and outwardly in a straight inclined plane.

3. In a ships davit, a frame having a rigid trackway inclined upwardly and outwardly in a straight line, a boom supported from said frame and adapted to swing in a vertical plane, a member pivotally connected to said boom intermediate of its length and adapted to travel on the inclined trackway of said frame, and means operatively connected with said pivotally connected member adapted to effect the swinging of the boom. I

4L. In a ships davit, a frame having a rigid trackway inclined upwardly and outwardly, a boom supported from said frame and adapted to swing in a vertical plane a member pivotally connected to said boom intermediate of its length and adapted to travel on the inclined trackway of said frame and a screw spindle journaled in said frame and engaging said pivotally connected member and adapted to move said member upon said trackway to effect the swinging of the boom.

5. In a ships davit, a frame having a rigid trackway inclined upwardly and outwardly, a carriage mounted on said trackway having a rolling contact therewith and depending flanges adapted to engage the sides of said trackway, a boom pivotally connected intermediate of its length to said carriage, and means for operating said carriage on said trackway.

THOMAS H. MARTEN. 

